The Gate of Haryana

Your planet is under the attack of aliens that have come from another planet. These aliens have to come to your planet after doing a lot of research. They know very well that they will have complete control over your planet once they have captured the main base that is protected by a line of electrical gate. It is only a matter of time for these aliens to cross the gate and enter the main base. You have the onus of stopping them from crossing the gate. Set up towers and units strategically. Launch attacks on the incoming enemies to eliminate them and prevent the invasion.